Question: What are the start and end dates of Greg Nickels as mayor of Seattle?
Paraphrase: What was the date that Greg Nickels became mayor of Seattle and on what date did his term as mayor of Seattle end?
SPARQL (Wikidata): SELECT ?value1 ?value2 WHERE { wd:Q5083 p:P6 ?s . ?s ps:P6 wd:Q330519 . ?s pq:P2032 ?value1 . ?s pq:P2031 ?value2 }